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<b><i><font face="Arial">Set Viewport</font></i></b>
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<p><font face="Arial Black"><font size=-1>Purpose</font></font>
<ul>The <b>Set Viewport</b> function selects a polygonal region of logical
coordinate space outside of which no primitives are rendered. The function
affects geometry which follows in the code.</ul>
<font face="Arial Black"><font size=-1>Syntax</font></font>
<br>&nbsp;
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<td VALIGN=TOP WIDTH="20%" HEIGHT="26" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Opcode
format</font></font></font></td>

<td VALIGN=TOP WIDTH="14%" HEIGHT="26" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Opcode</font></font></font></td>

<td VALIGN=TOP WIDTH="35%" HEIGHT="26" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Operand
Format</font></font></font></td>

<td VALIGN=TOP WIDTH="31%" HEIGHT="26" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Comments</font></font></font></td>
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<td VALIGN=TOP WIDTH="20%"><font face="Arial"><font size=-2>Extended ASCII</font></font></td>

<td VALIGN=TOP WIDTH="14%"><font face="Courier New"><font size=-2>(Viewport</font></font></td>

<td VALIGN=TOP WIDTH="35%"><b><font face="Courier New"><font size=-2>[&lt;ws>&lt;T<sub>Name</sub>>\</font></font></b>
<br><b><font face="Courier New"><font size=-2>[&lt;ws>&lt;I<sub>Count</sub>>[&lt;ws>&lt;I<sub>Xi</sub>>,&lt;I<sub>Yi</sub>>]<sup>+</sup>\</font></font></b>
<br><b><font face="Courier New"><font size=-2>&lt;ws>&lt;T<sub>Units</sub>>&lt;ws>\</font></font></b>
<br><b><font face="Courier New"><font size=-2>((&lt;F<sub>M00</sub>>&lt;ws>&lt;F<sub>M01</sub>>&lt;ws>&lt;F<sub>M02</sub>>&lt;ws>&lt;F<sub>M03</sub>>)\</font></font></b>
<br><b><font face="Courier New"><font size=-2>(&lt;F<sub>M10</sub>>&lt;ws>&lt;F<sub>M11</sub>>&lt;ws>&lt;F<sub>M12</sub>>&lt;ws>&lt;F<sub>M13</sub>>)\</font></font></b>
<br><b><font face="Courier New"><font size=-2>(&lt;F<sub>M20</sub>>&lt;ws>&lt;F<sub>M21</sub>>&lt;ws>&lt;F<sub>M22</sub>>&lt;ws>&lt;F<sub>M23</sub>>)\</font></font></b>
<br><b><font face="Courier New"><font size=-2>(&lt;F<sub>M30</sub>>&lt;ws>&lt;F<sub>M31</sub>>&lt;ws>&lt;F<sub>M32</sub>>&lt;ws>&lt;F<sub>M33</sub>>))]])</font></font></b></td>

<td VALIGN=TOP WIDTH="31%"><font face="Arial"><font size=-2>Specifies a
clipping region of the current viewing region.</font></font></td>
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<ul><i>Name&nbsp;&nbsp; </i>The name that identifies the viewport.
<p><i>Count&nbsp;&nbsp; </i>The number of points that define the viewport.
When using the binary operand form, a value of zero for <i>count </i>indicates
that an extended count will follow. In the ASCII operand case, <i>count
</i>may
be any value larger than zero.
<p><i>X<sub>i </sub>,Y<sub>i&nbsp;&nbsp; </sub></i>The <i>i</i><sup>th
</sup>point
(in logical coordinates) that circumscribe a region defining the viewport
<p><i>Units&nbsp;&nbsp; </i>If the viewport is changing the scale of the
subsequent geometry, then a <a href="DefDwgUnits.html">Units</a> opcode
will be inserted.</ul>
<font face="Arial Black"><font size=-1>Details</font></font>
<ul>The Viewport opcode specifies a sub-region of the current viewing-region
with which to clip and scale subsequent viewing primitives until the viewport
is deactivated.
<p>To deactivate the viewing region, the Viewport opcode is presented without
any arguments:
<dir><font face="Courier New"><font size=-1>(Viewport)</font></font></dir>
To reactivate a previously defined viewing region, the Viewport opcode
is presented with only its name:
<dir><font face="Courier New"><font size=-1>(Viewport 'Uncle Ed's Viewport')</font></font></dir>
</ul>
<font face="Arial Black"><font size=-1>Notes</font></font>
<ul>Non-rectangular viewing-regions may be handled by defining the viewport
region to be non-rectangular.</ul>
<font face="Arial Black"><font size=-1>Default</font></font>
<ul>By default no viewing-region is performed and the entire logical coordinate
space may be viewed.</ul>
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